Buggy code:
@ Controller public class DBInitializatorController { private static boolean initialized = false ; private static int numProfessors = 2 ; private static int numUser = ( DBInitializatorController . numProfessors ) * ( DBInitializatorController . numProfessors ) ; private static int ageForProfessor = 30 ; private static int ageForStudent = 19 ; private static int lectureForCfu = 2 ; private static float attendanceStudentProbability = 0.75F ; private static float lectureMaterialProbability = 0.75F ; private static float homeworkStudentProbability = 0.75F ; private static float questionStudentProbability = 0.1F ; private static float questionProfessorProbability = 0.05F ; private static float answerStudentProbability = 0.5F ; private static float answerProfessorProbability = 0.8F ; private static float eventUserProbability = 0.05F ; private static float professorCommunicationsProbability = 0.02F ; private static float questionAttachmentProbability = 0.02F ; private static float answerAttachmentProbability = 0.02F ; private static float homeworkAttachmentProbability = 0.02F ; private static float homeworkStudentSolvingAttachmentProbability = 0.02F ; private static Random random = new Random ( ) ; @ Autowired ApplicationContext appContext ; private static final Logger logger = LoggerFactory . getLogger ( HomeController . class ) ; @ RequestMapping ( value = "//db_init" , method = RequestMethod . GET ) public String dbInitialization ( Locale locale , Model model , HttpServletRequest request ) { } private void dbUserStudentProfessorInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbDegreeCourseDepartmentInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbCourseClassInit ( Locale locale , Model model , HttpServletRequest request ) { } @ SuppressWarnings ( "deprecation" ) private void dbRegistrationStudentClassInit ( Locale locale , Model model , HttpServletRequest request ) { } @ SuppressWarnings ( "deprecation" ) private void dbLectureInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbAttendanceStudentLectureInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbMaterialInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbHomeworkInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbHomeworkStudentSolvingInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbQuestionAnswerInit ( Locale locale , Model model , HttpServletRequest request ) { } @ SuppressWarnings ( "deprecation" ) private void dbExamInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbStudentExamPartecipationInit ( Locale locale , Model model , HttpServletRequest request ) { } @ SuppressWarnings ( "deprecation" ) private void dbEventInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbCommunicationInit ( Locale locale , Model model , HttpServletRequest request ) { DBInitializatorController . logger . info ( "Communications<seq2seq4repair_space>creation..." , locale ) ; CommunicationsDAO communicationsDAO = DaoHelper . getCommunicationsDAO ( ) ; UserDAO userDao = DaoHelper . getUserDAO ( ) ; int k = 0 ; for ( Professor professor : userDao . getAllProfessors ( ) ) { if ( ( DBInitializatorController . random . nextFloat ( ) ) <= ( DBInitializatorController . professorCommunicationsProbability ) ) { int numCommunications = DBInitializatorController . random . nextInt ( 3 ) ; for ( int i = 0 ; i < numCommunications ; i ++ ) { <START_BUG> Communications communications = new Communications ( k , ( "Communication" + k ) , ( "Description" + k ) , professor ) ; <END_BUG> communicationsDAO . create ( communications ) ; DBInitializatorController . logger . info ( ( "Created<seq2seq4repair_space>" + communications ) , locale ) ; k ++ ; } } } } private void dbQuestionAttachedContentInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbAnswerAttachedContentInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbHomeworkAttachedInit ( Locale locale , Model model , HttpServletRequest request ) { } private void dbHomeworkAttachedStudentSolvingInit ( Locale locale , Model model , HttpServletRequest request ) { } }

Fix:
Communications communications = new Communications ( k , ( "Communication" + k ) , ( "Description" + k ) , professor , Calendar . getInstance ( ) . getTime ( ) ) ;